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Related papers: Five open problems in quantum information

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Convex optimization problems arise naturally in quantum information theory, often in terms of minimizing a convex function over a convex subset of the space of hermitian matrices. In most cases, finding exact solutions to these problems is…

Quantum Physics · Physics 2014-11-26 Mark W. Girard , Gilad Gour , Shmuel Friedland

In quantum-state tomography on sources with quantum degrees of freedom of large Hilbert spaces, inference of quantum states of light for instance, a complete characterization of the quantum states for these sources is often not feasible…

Quantum Physics · Physics 2013-11-14 Yong Siah Teo , Jaroslav Rehacek , Zdenek Hradil

The quantum prepare-and-measure scenario has been studied under various physical assumptions on the emitted states. Here, we first discuss how different assumptions are conceptually and formally related. We then identify one that can serve…

Quantum Physics · Physics 2025-02-19 Jef Pauwels , Stefano Pironio , Armin Tavakoli

We study the reachability problem of a quantum system modelled by a quantum automaton. The reachable sets are chosen to be boolean combinations of (closed) subspaces of the state space of the quantum system. Four different reachability…

Logic in Computer Science · Computer Science 2014-01-27 Yangjia Li , Mingsheng Ying

Some open questions in quantum information theory (QIT) are described. Most of them were presented in Banff during the BIRS workshop on Operator Structures in QIT 11-16 February 2007. New material has been added in view of the recent…

Quantum Physics · Physics 2007-08-15 Mary Beth Ruskai

Quantum information is a rapidly advancing area of interdisciplinary research. It may lead to real-world applications for communication and computation unavailable without the exploitation of quantum properties such as nonorthogonality or…

Quantum Physics · Physics 2009-11-10 Samuel L. Braunstein , Peter van Loock

Quantum information science explores the frontier of highly complex quantum states, the "entanglement frontier." This study is motivated by the observation (widely believed but unproven) that classical systems cannot simulate highly…

Quantum Physics · Physics 2012-11-13 John Preskill

The agenda of quantum algorithmic information theory, ordered `top-down,' is the quantum halting amplitude, followed by the quantum algorithmic information content, which in turn requires the theory of quantum computation. The fundamental…

Quantum Physics · Physics 2007-05-23 Karl Svozil

We propose and discuss two conjectures on the nature of information leaks (decoherence) for quantum computers. These conjectures, if (or when) they hold, are damaging for quantum error-correction as required by fault-tolerant quantum…

Quantum Physics · Physics 2008-06-17 Gil Kalai

Quantum mechanics---the theory describing the fundamental workings of nature---is famously counterintuitive: it predicts that a particle can be in two places at the same time, and that two remote particles can be inextricably and…

Computing accessible information for an ensemble of quantum states is a basic problem in quantum information theory. We show that the recently obtained optimality criterion (A.S. Holevo, Lobachevskii J. Math., \textbf{43}:7 (2022),…

Quantum Physics · Physics 2026-01-30 A. S. Holevo , A. V. Utkin

The ability to extract relevant information is critical to learning. An ingenious approach as such is the information bottleneck, an optimisation problem whose solution corresponds to a faithful and memory-efficient representation of…

Quantum Physics · Physics 2023-03-08 Masahito Hayashi , Yuxiang Yang

Information, in its communications sense, is a transactional property. If the received signals communicate choices made by the sender of the signals, then information has been transmitter by the sender to the receiver. Given this reality,…

Quantum Physics · Physics 2012-08-07 Subhash Kak

In this brief note, I will consider the following questions: (1) What is QIP? (2) Why QIP is interesting? (3) What QIP can do? (4) What QIP cannot do? (5) What are the major challenges in QIP?

Quantum Physics · Physics 2007-05-23 Hoi-Kwong Lo

Quantum information is about the entanglement of states. To this starting point we add parameters whereby a single state becomes a non-vanishing section of a bundle. We consider through examples the possible entanglement patterns of…

Quantum Physics · Physics 2023-11-23 M. H. Freedman , M. B. Hastings

The ability to harness the dynamics of quantum information and entanglement is necessary for the development of quantum technologies and the study of complex quantum systems. On the theoretical side the dynamics of quantum information is a…

Quantum Physics · Physics 2019-09-02 R. J. Lewis-Swan , A. Safavi-Naini , A. M. Kaufman , A. M. Rey

Given an unknown quantum state distributed over two systems, we determine how much quantum communication is needed to transfer the full state to one system. This communication measures the "partial information" one system needs conditioned…

Quantum Physics · Physics 2007-05-23 Michal Horodecki , Jonathan Oppenheim , Andreas Winter

In this chapter we explore the connection between mesoscopic physics and quantum computing. After giving a bibliography providing a general introduction to the subject of quantum information processing, we review the various approaches that…

Mesoscale and Nanoscale Physics · Physics 2007-05-23 D. P. DiVincenzo , G. Burkard , D. Loss , E. V. Sukhorukov

Thermodynamic entropy is not an entirely satisfactory measure of information of a quantum state. This entropy for an unknown pure state is zero, although repeated measurements on copies of such a pure state do communicate information. In…

Quantum Physics · Physics 2015-06-26 Subhash Kak

From the perspective of quantum information theory, a system so simple as one restricted to just two nonorthogonal states can be surprisingly rich in physics. In this paper, we explore the extent of this statement through a review of three…

Quantum Physics · Physics 2007-05-23 Christopher A. Fuchs